sure thats late night for me my eyes were closing...
if these motors overheat a little from a small problem it becomes a big problem.
lets do a couple scenarios;
#1. blown HG (head gasket) lets cylinder compression into the cooling system. builds pressure and blows out a heater core seam spilling coolant.
#2 blown HG leaks coolant into cylinder and is combusted and expelled out the exhaust as steam.
#3 blown HG leaks compression into the cooling system, pressure forces coolant out the overflow, overflow is always full but radiator is empty.
now a failed component like a water pump could lead to a blown HG but usually the other way. a thermostat can be slammed closed by the pressure that is generated causing issues but the source is the HG. these components are made to withstand much more abuse they they naturally receive without other forces compromising them.
I hope this is the paragraph that you mentioned if not just quote my ramblings ill try to explain
i error-ed in my statement about valves, it blows near the exhaust valve not to the exhaust valve, and cracks between the valves.
